A variety of mechanical devices have been developed for inter-engaging a knife and sheath while still permitting a quick release. Such interlocking features are important for the sporting uses and are particularly important for underwater divers who must be able to insert and remove a knife from a sheath quickly and efficiently while assured the knife will not slip from the sheath.
A variety of devices have been developed including one in which the blade is simply engaged in the sheath pocket by frictional engagement. That arrangement, is not satisfactory for underwater use because the blade may readily lose its frictional engagement with the sheath and slide out while the swimmer is moving through the water.
Another form of knife and sheath combines a strap that engages the knife handle and is secured by a snap fastener or the like. That configuration is not satisfactory for underwater use because the snap is not always properly fastened securely and because the user frequently will not be able to see or readily feel the snap underwater, especially when wearing gloves.
Other combinations include pushbuttons which are spring loaded to snap into engagement. Such knife and sheath combinations are exemplified by co-pending application Ser. No. 115,059, filed Oct. 10, 1987 and references cited during the prosecution of that application including, Widen, U.S. Pat. No. 2,901,823, issued Sep. 1, 1959, Collins, U.S. Pat. No. 4,404,747, issued Sep. 20, 1983 and Housinger U.S. Pat. No. 2,391,574, issued Dec. 25, 1945. Each of these issued patents and the co-pending application provide interlocks in which springloaded detents inter-engage a sheath or similar holder. While such arrangements may adequately provide an interlock with a rapid release mechanism, the constructions either involve an assembly of components during manufacturing or involve the use of moving parts when in use. For example, in the Widen U.S. Pat. No. 2,901,823, there is provided a spring detent which is secured to a sheath by riveting assembly, which in combination with a sliding bolt in the handle, provides a mechanism for release. The Collins U.S. Pat. No. 4,404,747, has a springloaded button assembled into the handle with this button adapted to project into a hole in the scabbard. The unit requires the manufacture of a number of different components and assembly. The Housinger U.S. Pat. No. 2,391,574, also involves an assembly of a springloaded detent which is riveted to a scabbard.